What is a Domain?

People who self-host a WordPress website also need to register a domain, such as mywebsite.com. A domain is a sort of forwarding address that gets people to your website.

As we remember from What is a Website?, a website is made up of files that are stored on a computer connected to the internet, called an internet server. A web browser on a computer or phone uses the internet to download the website files from the internet server to the device so that the website visitor can view the website.

But among the billions of devices connected to the internet, how does the browser find the right server to download the files from?

A URL is Just a Forwarding Address

The URL is the address of a website, right? Well, not exactly. The URL does not, in itself, contain any location information about where the website’s files are stored. Rather, it is a human-friendly search term to look up that location. The real address for a website, which identifies the server where the website’s files are hosted, is in a numerical format. One of the things web browsers do is communicate with internet directory computers that convert the human-friendly URL address into a numerical address that actually tells the browser where on the internet to find the website’s files.

Name Servers – Ushers of the Internet

When you type a URL into a browser, or click on a link, the browser contacts the internet service provider for the device – your ISP if you are at home, your cell service provider if you are browsing from your phone, or your company’s ISP if you are at work. The browser’s first stop is an internet directory computer provided by your ISP that is called a DNS resolver.

The DNS resolver looks up the URL to convert it to a numerical address. It is this numerical address that contains the internet location of the company that is currently hosting the files for that website. The DNS resolver directs your browser to the name server of that webhost.

A name server is a traffic directing computer. Your browser queries the webhost’s name server for the address of the specific server that has the website files (since webhosts have lots of servers, and they each have a different internet address). Then your browser connects to the server with the files, downloads them, and displays the website.

Your never realized there was so much going on when you clicked a link, did you? And it all happens very rapidly, and entirely behind the scenes.

This system may seem overly convoluted, but it allows website owners to change web hosts without having to change their URL – all they have to do is update the location information for the server with the website files in the directory servers (this is sometimes called “pointing” a domain). Web surfers never need to think about what server a website is on.

Can You Run That By Me Again?

Still lost? Imagine we are making a long distance phone call in a 1940s movie. First, we would be connected to the switchboard operator for our own town (the DNS resolver). That operator connect us to the operator for the city we want to call (the “switchboard” for the webhosting company where the website files are hosted). The webhost switchboard operator would connect us to the specific extension (the specific server within that company that holds the files of the website we want to view).

Your Domain is Not Really Yours

Like web hosting, domain registration is on a rental basis. Even though registering a domain is often referred to as “buying” it, and the buyer is referred to as the domain “owner,” the domain is only yours for as long as you pay an annual fee. If you stop paying, the domain becomes available for someone else to rent, and they will “point” the domain to their own files on their web host’s server, leaving your files all dressed up for company, with no road to their door!

Note that domain names that include a trademark (such as the name of a large company or high-profile individual) cannot be used without the permission of the trademark holder even if the domain is available for registration.

Domain vs. URL

Are “domain” and “URL” the same thing? No. A domain is the core address for all of the pages on your website, while a URL is a link for a specific page or document in the domain. The URL for each page on a website includes the domain, plus additional information to differentiate it from other pages on the same domain.

Most websites use the domain as the home page URL. For example, the home page for MyWebsite might be mywebsite.com. But all the other pages on my website need to have their own URLs, so the URL for my contact page would be mywebsite.com/contact, for my About Me page would be mywebsite.com/about, and for individual posts would be mywebsite.com/the-title-of-my-post/ (assuming you have set your permalinks as suggested in this post). Visit the different pages on this website and observe the different URLs.